The Jewish year is not the same length as a solar year used by most of the western world. Months are either 29-30 days, corresponding to the 29½-day lunar cycle. Years are either 12 or 13 months, corresponding to the 12.4 month solar cycle. The Jewish calendar uses a 12-month lunar calendar with an extra month occasionally added. Jews do not generally use the words A.D. and B.C. Instead, C.E. (Common or Christian Era) and B.C.E. (Before the Common Era) are commonly used by scholars today.
Shalom! Today is 19 Av 5776. (20 Av 5776 after sunset.) This site offers free Jewish calendars you can download and print. They include Jewish holidays, and optionally include both Jewish and Gregorian (civil) dates, making it easy to keep track of both calendars at once.
Sukkot (Feast of Tabernacles) is a biblical holiday celebrated on the 15th day of the month of Tishrei (variously from late September to late October). It is one of the three biblically mandated festivals Shalosh Regalim on which Hebrews were commanded to make a pilgrimage to the Temple in Jerusalem. It follows the solemn holiday of Yom Kippur, or the Day of Atonement. http://www.fivefoldministryireland.com